Game crashes on launch on some devices

I am experiencing a very strange issue.

I have a scene that, when deployed to the device (either via the Launch button or via iTunes) crashes after Launch. There is a brief moment, when I can see my scene and hear it’s sounds, before it crashes.

The problem started on 4.10.1 and still continues in the 4.11 Preview

On my test devices, I experience the crash only on iPhone 6 Plus (iOS 9.2). Its runs fine on a and an iPad 3.

Initially I though it was something to do with the Metal Forward Rendering, so I disabled it, but I am still experience the crash.

The log I’ve fetched from the device doesn’t so anything. See [attached][1]

Some info on the scene: Contains a landscape created in World Machine (253X253) with a simple shader with 2 layers and 5 textures (2 custom UVs). Has static lighting only. All materials are fully rough. All textures are either 512X512 or 1024X1024 (i’ve followed all the guidelines for mobile development)

Other projects work fine in my iPhone 6 Plus.

72516-om.log (16 KB)

I am very close to release this project and this issue is holding me back for two weeks now. Any help is highly appreciated!

Another thing I discovered about this issue… It runs on the iPhone 6 Plus without crashing, if setting in DeviceProfiles to run in half resolution

Hey Romfeo,

Would you be able to upload the sample project for me to look into further? The provided aren’t full, they do not seem to show where the application crashed on the device. You will not be able to upload it to AnswerHub, you may want to use or Drive.

If you’re not able to share your project with me, could you please provide me the full reproduction steps in order to replicate this on my end?

Thanks!

Hi ,

Thanks for coming back to me. I am not able to upload my project, since it is not a test project but a project near to its completion.

Yes, the do end abruptly. I was not able to retrieve any additional info either.

I will try to create a test project that has the same behavior and upload that in the next 24 hours. Does that sound ok?

Sounds perfect, thank you!

Hi again ,

It is actually very simple to reproduce this crash. So in order to save you from the burden of downloading a huge file, I will just outline the steps here.

  1. Run 4.10.1 (Launcher version) and create a new, blank project. You can also test it with 4.11 Preview…Same crash
  2. Set Target Hardware to Mobile/ Tablet and quality to Maximum
  3. Now, you need a complex scene. To make it easier, in my test I’ve used the FrozenCove map from the Infinity Blade: Ice Lands assets.
  4. Create a DefaultDeviceProfiles.ini in the config folder of your project and make sure that you have +CVars=r.MobileContentScaleFactor=2 set for the device
  5. In my test, I have used an existing & valid iOS bundle identifier and equivalent certificate and provision profile in iOS settings.
  6. Also, in IOS settings Support Forward rendering with Metal is checked. Supports Open GLES2 is checked. Unchecking Metal doesn’t seem to solve the issue.
  7. Launch the map on the device and enjoy the crash!

As a summary, a few additional info…

I am testing this on a Mac Pro running OSX El Capitan v. 10.11.2. The device affected from the crash is an iPhone 6 Plus running iOS 9.2
The project runs on an iPad 3 (its a device that doesn’t supports Metal) and on an (android).
The project runs on iPhone 6 Plus ONLY if +CVars=r.MobileContentScaleFactor is set to 1, forcing the project to run in half the resolution of the device.

Looking forward for your reply, because everything is ready for release and this crash is a show stopper!

Thanks again for all your help!

Romfeo,

I changed the +CVars=r.MobileContentScaleFactor to 2 and did not have any trouble with the or the iPhone 6S Plus. Would you mind providing me with your DefaultDeviceProfiles.ini file that you created? Perhaps I missed an area by mistake. I’d like to compare.

Thanks!

Hi ,

Thank you so much for your efforts. I am attaching my DefaultDeviceProfiles.ini, but I am pretty sure that is not what causing the problem.[DefaultDeviceProfiles.ini][1]

I am thinking that there are two possible causes left:

  1. Something is wrong with my iPhone 6 Plus. I doubt it, because I don’t have any other problems with it, but I will try to find some more devices to do some tests.
  2. There is something going wrong when running the project on devices equipped with the A8 Processor (such as iPhone 6, iPhone 6 Plus, iPad Air 2, iPad Mini 4). Is there any way you can perform a test to such a device, just to narrow our possibilities down?

Thanks again!!!

73343-defaultdeviceprofiles.ini.zip (837 Bytes)

Hi ,

These are very bad news… Can you please provide some more information on the problem?

Is there a way around this problem, since my other option is to postpone the release of my project for a few weeks, which is devastating and very costly!!!

Thanks again

Is the iPhone 6 Plus the only device affected?

As far as I know it is not possible to prohibit a specific model from downloading an app from the App Store.

Just saying in the app store description that the app is not working on the iPhone 6 Plus is very unprofessional, it will be ignored by many people and I will just end up having a bunch of bad reviews from angry customers…

I am afraid, since you can’t release any more info that would maybe help me to create another temporary solution, that I will have to do a very costly cancellation of out launch plans and postpone it for an unknown date.

Romfeo,

Thanks for providing me all of the information and files that you did. I have been able to verify this and I have entered a for the issue. UE-25199 has been assigned to the bug. Feel free to check on this issue in a few weeks.

Thank you!

At this time, I do not have any additional information to provide. I will update this post as soon as I hear more information from our developers. If you’re trying to release, you may want to mark it down for now as not working on the iPhone 6 Plus.

I checked , , Lenovo S939 as well as the Samsung Galaxy Note 2. The only device I found that it didn’t work on was the iPhone 6 Plus.

I will let you know if I see any updates with the report, thank you.

I’ve been looking at this today. On Metal it is failing because MSAA is enabled and it is not properly creating a texture for it. On OpenGL it is working fine for me with a scale factor of 2 (if fine is a black screen with the virtual joysticks, but no crash). However, the log posted with this issue is showing a scale factor of 0 (which means use the optimal scale factor of 2.6). Even with that I am still not failing on OpenGL with 4.11 Preview 4.

In order for the crash to occur, you must have a complex scene. On simple scenes it doesn’t crash for me either. Additionally, this is device specific. So far, we have identified the crash to occur only on iOS devices with the A8 CPU. The crash occurs on both scale factors, 0 and 2

I am testing this on an iPhone 6 Plus. Even if I figure this out today, I don’t recommend trying to release a game with any engine preview. Set your Mobile Scale Factor to 1 and release your game. You can always update it once there is a good fix which should happen before 4.11 is released.

-Pete

Thanks for that Pete. We were investigating the possibility of releasing the game with Scale Factor set to 1, but there are some key things that doesnt look good on that resolution. So we have to wait for a fix…

I just opened the Frozen Cove map on an iPhone 6 Plus with scale factor 0 and it opened fine in OpenGL. Is there a different map I should be trying?

This is a map that was crashing to both and me on a 6 Plus. I assume you tried it on 4.10.2 with Metal disabled?

No, I haven’t tried it in 4.10.2, plus Metal is a different issue with MSAA. I’ll be looking in to that in a moment, but I wanted to get the crash in both before focusing on one fix over the other. I would suggest for Metal disabling MSAA, but I don’t remember if we made that a setting anywhere in the editor.